The present invention relates to the detection of organic compounds in solutions and is widely applicable for chemical and clinical analysis and for monitoring of fermentation processes and waste water treatment. The method of measuring optical absorbance has been, in general, used for detecting organic compounds, but this method requires complicated technical manipulation and long assaying times. Therefore, bio-sensors, which could specifically and rapidly detect organic compounds have recently been developed by using immobilized enzymes and an electrochemical detector. For bio-sensors, the particular electrochemical device that is used for detection is determined by the type of enzyme reaction. This is one of the drawbacks of electrochemical bio-sensors, because they can not use the common electrochemical sensor for various enzyme reactions.
The enzyme thermistor system, which is constructed by using an immobilized enzyme column a, thermistor a, heat-exchanger and a high sensitivity thermostatic bath, has been invented as a multifunction bio-sensor system, for detecting enthalpy change that occurs in all enzyme reactions. Several enzyme thermistor systems have been developed and reported, one of them being reported in the following document: Klaus Mosbach, Bengt Danielsson. Anal. Chem. Vol. 53 No. 1 (1981), Page 83A to 94A.
The thermistor used in the enzyme thermistor system has excellent sensitivity to temperature change, but it has several inherent problems; the characteristics curve between temperature and resistance exhibits poor lineality; selfheating of the thermistors creastes unavoidable experimental error and; for, these reasons, the sensor system must be large.